The present invention is directed to a dry cleaning composition, more specifically, to a siloxane fluid based composition, for use in dry cleaning and to a dry cleaning process using the composition.
Current dry cleaning technology uses perchloroethylene (xe2x80x9cPERCxe2x80x9d) or petroleum-based materials as the cleaning solvent. PERC suffers from toxicity and odor issues. The petroleum-based products are not as effective as PERC in cleaning garments.
Cyclic siloxanes have been reported as spot cleaning solutions, see U.S. Pat. No. 4,685,930, and as dry cleaning fluids in dry cleaning machines, see U.S. Pat. No. 5,942,007. Other patents disclose the use of silicone soaps in petroleum solvents, see JP 09299687, and the use of silicone surfactants in super critical carbon dioxide solutions has been reported, see, for example, U.S. Pat. No. 5,676,705 and Chem. Mark. Rep., Dec. 15, 1997, 252(24), p. 15. Non-volatile silicone oils have also been used as the cleaning solvent requiring removal by a second washing with perfluoroalkane to remove the silicone oil, see JP 06327888.
Numerous other patents have issued in which siloxanes or organomodified silicones have been present as addenda in PERC or petroleum based dry cleaning solvents, see, for example, WO 9401510; U.S. Pat. Nos. 4,911,853; 4,005,231; 4,065,258.
There is a continued interest in providing an additive or additives to enhance the cleaning ability of silicone based dry cleaning solvents.
In a first aspect, the present invention is directed to a dry cleaning composition, comprising a volatile siloxane and one or more aminofunctional siloxanes.
In a second aspect, the present invention is directed to a method for dry cleaning comprising contacting an article with a composition comprising a volatile siloxane and an aminofunctional siloxane.
The process of the present invention exhibits improved performance, such as for example, removal of water soluble stains from the article, for example a garment, being cleaned. The process of the present invention also exhibits improved performance for removal of soluble stains, including oil stains and grease stains.
In a preferred embodiment, the composition comprises, based on 100 parts by weight (xe2x80x9cpbwxe2x80x9d) of the composition, from greater than 90 pbw to 99.999 pbw, more preferably from 92 pbw to 99.9 pbw and even more preferably from 95 pbw to 99.5 pbw of the volatile siloxane and from 0.001 pbw to less than 10 pbw, more preferably from 0.01 pbw to 8 pbw and even more preferably from 0.1 pbw to 5 pbw of the aminofunctional siloxane or siloxanes. The volatile siloxane may be linear, branched, cyclic, or a combination thereof. The composition optionally further comprises water, preferably from 0.01 pbw to 15 pbw, more preferably from 0.1 pbw to less than 12 pbw and even more preferably from 0.2 pbw to 10 pbw of water. Preferably, the composition does not include siloxane resins or crosslinking agents. The composition optionally further comprises acid in amounts sufficient to protonate the amino functionality of the aminofunctional silicone.
In a preferred embodiment, the water may be added as xe2x80x9cfreexe2x80x9d water or may be delivered by an emulsion containing other components such as siloxanes, hydrocarbons, surfactants, or other suitable additives. If the water is delivered by an emulsion, the emulsion may be prepared by either homogenization of the components or by mechanically stirring the mixture.
Compounds suitable as the linear or branched, volatile siloxane solvent of the present invention are those containing a polysiloxane structure that includes from 2 to 20 silicon atoms. Preferably, the linear or branched, volatile siloxanes are relatively volatile materials, having, for example, a boiling of below about 300xc2x0 C. point at a pressure of 760 millimeters of mercury (xe2x80x9cmm Hgxe2x80x9d).
In a preferred embodiment, the linear or branched, volatile siloxane comprises one or more compounds of the structural formula (I):
M2+y+2zDxTyQzxe2x80x83xe2x80x83(I)
wherein:
M is R13SiO/1/2;
D is R2R3SiO2/2;
T is R4SiO3/2;
and Q is SiO4/2 
R1, R2, R3 and R4 are each independently a monovalent hydrocarbon radical; and
x and y are each integers, wherein 0xe2x89xa6xxe2x89xa610 and 0xe2x89xa6yxe2x89xa610 and 0xe2x89xa6zxe2x89xa610.
Suitable monovalent hydrocarbon groups include acyclic hydrocarbon radicals, monovalent alicyclic hydrocarbon radicals, monovalent and aromatic or fluoro containing hydrocarbon radicals. Preferred monovalent hydrocarbon radicals are monovalent alkyl radicals, monovalent aryl radicals and monovalent aralkyl radicals.
As used herein, the term xe2x80x9c(C1-C6)alkylxe2x80x9d means a linear or branched alkyl group containing from 1 to 6 carbons per group, such as, for example, methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, pentyl, hexyl, preferably methyl.
As used herein, the term xe2x80x9carylxe2x80x9d means a monovalent unsaturated hydrocarbon ring system containing one or more aromatic or fluoro containing rings per group, which may optionally be substituted on the one or more aromatic or fluoro containing rings, preferably with one or more (C1-C6)alkyl groups and which, in the case of two or more rings, may be fused rings, including, for example, phenyl, 2,4,6-trimethylphenyl, 2-isopropylmethylphenyl, 1-pentalenyl, naphthyl, anthryl, preferably phenyl.
As used herein, the term xe2x80x9caralkylxe2x80x9d means an aryl derivative of an alkyl group, preferably a (C2-C6)alkyl group, wherein the alkyl portion of the aryl derivative may, optionally, be interrupted by an oxygen atom, such as, for example, phenylethyl, phenylpropyl, 2-(1-naphthyl)ethyl, preferably phenylpropyl, phenyoxypropyl, biphenyloxypropyl.
In a preferred embodiment, the monovalent hydrocarbon radical is a monovalent (C1-C6)alkyl radical, most preferably, methyl.
In a preferred embodiment, the linear or branched, volatile siloxane comprises one or more of, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, tetradecamethylhexasiloxane or hexadecamethylheptasiloxane or methyltris(trimethylsiloxy)silane. In a more highly preferred embodiment, the linear or branched, volatile siloxane of the present invention comprises octamethyltrisiloxane, decamethyltetrasiloxane, or dodecamethylpentasiloxane or methyltris(trimethylsiloxy)silane. In a highly preferred embodiment, the siloxane component of the composition of the present invention consists essentially of decamethyltetrasiloxane.
Suitable linear or branched volatile siloxanes are made by known methods, such as, for example, hydrolysis and condensation of one or more of tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, or by isolation of the desired fraction of an equilibrate mixture of hexamethyldisiloxane and octamethylcyclotetrasiloxane or the like and are commercially available.
Compounds suitable as the cyclic siloxane component of the present invention are those containing a polysiloxane ring structure that includes from 2 to 20 silicon atoms in the ring. Preferably, the linear, volatile siloxanes and cyclic siloxanes are relatively volatile materials, having, for example, a boiling point of below about 300xc2x0 C. at a pressure of 760 millimeters of mercury (xe2x80x9cmm Hgxe2x80x9d).
In a preferred embodiment, the cyclic siloxane component comprises one or more compounds of the structural formula (II): 
wherein:
R5, R6, R7 and R8 are each independently a monovalent hydrocarbon group; and
a and b are each integers wherein 0xe2x89xa6axe2x89xa610 and 0xe2x89xa6bxe2x89xa610, provided that 3xe2x89xa6(a+b)xe2x89xa610.
In a preferred embodiment, the cyclic siloxane comprises one or more of, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, tetradecamethylcycloheptasiloxane. In a more highly preferred embodiment, the cyclic siloxane of the present invention comprises octamethylcyclotetrasiloxane or decamethylcyclopentasiloxane. In a highly preferred embodiment, the cyclic siloxane component of the composition of the present invention consists essentially of decamethylcyclopentasiloxane.
Suitable cyclic siloxanes are made by known methods, such as, for example, hydrolysis and condensation of dimethyldichlorosilane and are commercially available.
The aminofunctional silicone comprises structural units of the formula:
R20fSiO4-f
wherein at least one R20 is xe2x80x94(CHR24)nNR25R26 where R24 is H or alkyl, preferably (C1-C8)alkyl, R25 is H or alkyl, preferably (C1-C4)alkyl, R26 is H, alkyl, preferably (C1-C8)alkyl, or xe2x80x94(CHR27)mNR28R29 where R27 is H or alkyl, preferably (C1-C8)alkyl and R28 and R29 are each independently H or alkyl, preferably (C1-C4)alkyl, n is from 2 to 16, and m is from 2 to 16; and 1xe2x89xa6fxe2x89xa63.
In a preferred embodiment, the aminofunctional silicone of the present invention comprises one or more siloxanes selected from block or random polymers and copolymers and terminally substituted aminofunctional siloxane polymers having the structural formula:
M*DxDxe2x80x2yTwTxe2x80x2zM*xe2x80x83xe2x80x83(I)
wherein
M* is R21R22R23SiO1/2, wherein each R21, R22 and R23 is independently alkyl, preferably (C1-C8)alkyl, aryl, substituted alkyl or aryl, alkoxy, preferably (C1-C8)alkoxy, xe2x80x94(CH2)a(CH2CH2O)b(CH2CH(CH3)O)cR15, wherein R15 is II or alkyl, preferably (C1-C8)alkyl, a is from 2 to 8 inclusive, b and c are each from 0 to 20 inclusive, or R20, as previously defined;
D is R142SiO2/2, wherein each R14 is alkyl, preferably (C1-C8)alkyl or xe2x80x94(CH2)a(CH2CH2O)b(CH2CH(CH3)O)cR15, wherein R15 is H or alkyl, preferably (C1-C8)alkyl, a is from 2 to 8 inclusive, b and c are each from 0 to 20 inclusive;
Dxe2x80x2 is R10R11SiO2/2, wherein R10 is alkyl, preferably (C1-C8)alkyl, aryl, or
xe2x80x94(CH2)a(CH2CH2O)b(CH2CH(CH3)O)cR15, wherein R15 is H or alkyl, preferably (C1-C8)alkyl, a is from 2 to 8 inclusive, b and c are each from 0 to 20 inclusive, and R11 is R20, as previously defined, or polyether, alkyl, aryl, or other functional side group;
T is R12SiO3/2, wherein R12 is alkyl or aryl, preferably (C1-C8)alkyl or xe2x80x94(CH2)a(CH2CH2O)b(CH2CH(CH3)O)cR15, wherein R15 is H or alkyl, preferably (C1-C8)alkyl;
Txe2x80x2 is R13SiO3/2, wherein R13 is alkyl, preferably (C1-C8)alkyl, aryl, or xe2x80x94(CH2)a(CH2CH2O)b(CH2CH(CH3)O)cR15, wherein R15 is H or alkyl, preferably (C1-C8)alkyl, a is from 2 to 8 inclusive, b and c are each from 0 to 20 inclusive, and R11 is R20, as previously defined, or polyether, alkyl, aryl, or other functional side group;
and w, x, y and z are integers such that 0xe2x89xa6wxe2x89xa640, 0xe2x89xa6xxe2x89xa6500, 0xe2x89xa6yxe2x89xa650, 0xe2x89xa6zxe2x89xa640.
Compounds suitable as the aminofunctional silicone of the present invention include, but are not limited to, aminoethylaminopropyl linear graft copolymer, aminoethylaminopropyl branched graft copolymer, aminoethylaminopropyl terminal linear polymers, aminoethylaminoisobutyl branched graft copolymers, aminoethylaminoisobutyl linear graft copolymers, aminoethylaminoisobutyl terminal linear polymers, aminopropyl graft linear copolymers, aminopropyl terminally substituted linear polymer, aminoethylaminopropyl linear graft terpolymer with ethylene oxide-propylene oxide side chain, and the like.
In a preferred embodiment, the aminofunctional silicone of the present invention is an aminoalkyl substituted siloxane compound which may or may not be polymeric, wherein the aminoalkyl substituent is terminally substituted, substituted on a repeating unit, or both terminally substituted and substituted on a repeating unit, of a polymeric or copolymeric species, such as an aminoalkyl terminally substituted linear siloxane, an aminoalkyl terminally substituted branched siloxane, a linear siloxane with aminoalkyl substitution on chain, a branched siloxane with an aminoalkyl substitution on chain, an aminoalkyl linear graft copolymer, an aminoalkyl branched graft copolymer, an aminoalkyl linear graft terpolymer, or an aminoalkyl branched graft terpolymer.
In one preferred embodiment, each R21, R22, R23 and R10 is (C1-C8)alkyl, R11 is (CH2)nNH(CH2)mNH2, and w and z are 0. In another preferred embodiment, each R21, R22, R23, R10 and R12 is (C1-C8)alkyl, R11 is (CH2)nNH(CH2)mNH2, R13 is a polyether, and w is 0. In another preferred embodiment, each R21, R22, R23, R10 and R15 is (C1-C8)alkyl, R11 is (CH2)nNH(CH2)mNH2, and w is  greater than 0. In another preferred embodiment, each R21, R22, R10 and R14 is (C1-C8)alkyl, R23 is (CH2)NH2, w, y and z are 0, and x is from 2 to 100, preferably 2 to 10, preferably x is 2 or 10.
In a preferred embodiment, the dry cleaning composition of the present invention further comprises a minor amount, preferably, less than 50 pbw per 100 pbw of the composition, more preferably, less than 10 pbw per 100 pbw of the composition, of one or more non-siloxane fluids. Suitable non-siloxane fluids include aqueous fluids, such as, for example, water, and organic fluids, for example, hydrocarbon fluids and halogenated hydrocarbon fluids.
In a preferred embodiment, the dry cleaning composition of the present invention further comprises a minor amount, preferably less than 10 pbw, more preferably less than 8 pbw, even more preferably less than 5 pbw per 100 pbw of the composition, of one or more surfactants. Suitable surfactants include organic surfactants such as anionic, nonionic, cationic and amphoteric surfactants, and silicone surfactants.
An article, such as for example, a textile or leather article, typically, a garment, is dry cleaned by contacting the article with the composition of the present invention. In a preferred embodiment, the articles to be cleaned include textiles made from natural fibers, such as for example, cotton, wool, linen and hemp, from synthetic fibers, such as, for example, polyester fibers, polyamide fibers, polypropylene fibers and elastomeric fibers, from blends of natural and synthetic fibers, from natural or synthetic leather or natural or synthetic fur.
The article and dry cleaning composition are then separated, by, for example, one or more of draining and centrifugation. In a preferred embodiment, separation of the article and dry cleaning composition is followed by the application of heat, preferably, heating to a temperature of from 15xc2x0 C. to 120xc2x0 C., preferably from 20xc2x0 C. to 100xc2x0 C., or reduced pressure, preferably, a pressure of from 1 mm Hg to 750 mm Hg, or by application of both heat and reduced pressure, to the article.
Testing for water soluble stain removal was accomplished using fabric swatches supplied by the International Fabricare Institute (xe2x80x9cIFIxe2x80x9d) (Silver Spring, Md.) that contained a water soluble dye. The color change of a swatch of this material was measured by a Minolta CR-300(copyright) Colorimeter using the Hunter Color Number difference calculations. The larger the change in Hunter Color Number (xcex94E), the greater the dye removal and the more efficient the cleaning.
The following examples are to illustrate the invention and are not to be construed as limiting the claims.